Safety-relevant switching functions in vehicles require redundancy. Redundancy is achieved in that for the same switching function at least two switching units are present in parallel, which are actuated at the same time. Electronic control circuits monitor the switching signals. If the redundant switching signals are not detected within a predetermined period of, for instance, 30 ms, an error is indicated.
In practice, the implementation of redundant switches places high demands on the mechanical precision. To ensure the actuation of the redundant switch units within a very short period, actuator and switch units must be aligned relative to each other very precisely. Nevertheless, it is possible that instead of several switch units only one of them is actuated, for instance when the actuator is blocked in its actuating stroke.
The invention resolves this problem with a redundant switch, which does not place high demands on the mechanical precision and nevertheless ensures a safe actuation of the redundant switch units within a very short period.